Per capita income in China would equal that of the US by 2031 if the Chinese economy continues to grow at its current pace, he said. With a projected population of about 1.4 billion at that time, a China as prosperous as the US would:

Burn 99 million barrels of oil a day, 18 per cent more than is now produced globally.

Consume two-thirds of the world's current grain harvest.

Use twice as much paper as the world currently produces.

Drive 1.1 billion cars, more than the world's 2005 fleet of 800 million - forcing it to pave roads and car parks equal to the area it now plants in rice.

"There go the world's forests," said Dr Brown, an honoured researcher who in 1974 founded the Worldwatch Institute, the first centre to focus on global environmental issues.

In a new book, Plan B 2.0, Dr Brown argues that economic growth in China and India will cause the world economy to collapse unless world leaders rapidly shift to renewable energy, resourcerecycling and efficient transportation. He says the present global economic trend (Plan A) is not sustainable.